Syringe



L. M. JONES SYRIN GE 2 Sheets-Sheet 1 Filed Aug. 1923 Deco 1 L M. JONES SYRINGE Filed Aug. 1, 1923 2 Sheets-Sheet 2 Patented Dec. 1, 1925 UNITED STATES 1,564,074 PATENT OFFICE.

LEONARD MARCUS JONES, OF DULWIOH, ENGLAND.

SYRINGE.

Application filed August 1, 1923. Serial No. 655,670.

To aZZ whom it may concern:

Be it known that I, LEONARD lrinnous Jones, a thiitish subject, residing at 22 Court Lane Gardens, Dulwich, in the county of London, England, have invented certain new and useful Improvements in Syringes, of which the following is a specification.

This invention relates to syringes, and more particularly to lire extinguishers of the kind wherein a pistonis employed to eject the fluid. As hitherto constructed such appliances suffer from the defect that when stored ready for use the fluid content leaks out through'the nozzle, and the present invention has for its object to provide an appliance of the type described wherein the above objection is overcome.

A further object of the invention is to provide within the syringe a device operating as a closure for the inner end of the outlet tube when the syringe is stored ready for use, but adapted to be released from or moved out of the closing position when the syringe is required to operate. A further object of the invention is to operate said leak closing device through the medium of an elastic link and to house said device in a housing contained in an air pressure chamber and a further object is to situate said chamber at the forward end of the syringe. A further object is to render said device easily accessible on the removal of the nozzle. In the preferred form, the said closure is maintained in its operative closing position by means of the depressed piston. In this connection it is known in fire extinguishers of the type described to provide that the piston is fully depressed when the device is being stored, and is caused to en gage with a part of the casing so as to remain depressed until released from such en-- gagement when the extinguisheris required for use. p

In the drawings:

Fig. 1 is a sectional view of theimproved syringe.

Fig. 2 is an enlarged sectional view of the delivery end of such syringe.

In the drawings, the syringe illustrated, comprises an outer casing 20, divided by a partition 21 into two chambers, namely a liquid chamber 22, and an air cushion chamber 23, the latter being positioned at the de livery end of the syringe. A cylindrical housing 1 passes axially through the casing and serves as a pump chamber in which the piston 2 reciprocates. The piston rod emerges from the casing to a fitting 26 comprising an annular passage 27 leading to an enlarged chamber 28. The side walls of the passage 27 are pro'videdwith two slots 29 in which are adapted to enterlugs 30 formed on the handle of the piston rod, so that the latter can be pushed to the full extent of its stroke and rotated, whereupon the lugs 80 will be held within the chamber 28 and the piston be prevented from rising. In use, on'the operation of the piston 2, liquid is drawn through one of the gratings 31, 32, according to the inclination of the syringe, and delivered by I the pump through the pipe 83 into the air cushionchamber 28, whence it passes through the sieve 25 and tube 24: to the nozzle. The syringe is operated with the tube 24 directly downwardly, and owing to the provision of a cushion of air inthe chamber 23, the liquid is delivered from the nozzle in a constant flow.

Referring now particularly to Fig. 2 of the drawing, the tubular housing 1 in which the piston 2 is adapted to recipr cats is closed intermediate its length by a holed plug 3' and at the bottom by a removable plug constituting the nozzle 4. Between said plug and said nozzle the housing 1 encloses a chamber 5 through which the fluid contents of the extinguisher are required to pass to the outlet of the nozzle 4 Within the said chamber, I provide a closing device forming the object of this inven tion which preferably comprises two separate partsb, 6 The first part comprises a cylindrical body 7 having its outer end, that is, the end directed towards the nozzle, enlarged to form a hollow cylinder 8 of which the neck is externally shaped to the form of a cone or of a truncated cone 8 adapted toengage ina similarly-shaped face 3 in the corresponding wall of the plug. The inner end of the portion 7 is adapted to be 'engagedand depressed by the piston 2 when the latter is depressed below. the position shown; but the piston is illustrated as at the bottom of its normal stroke and is only intended to be further depressed during stor- Within the said cylinder Sis adapted to slide an enlargement 9 formed on the inner end of the member6 the parts 8, 9 being urged apart by a spring 10. The outer end 11 of the part 6" slides within the central passage 12 of the nozzle 4, making a liquidtight joint therewith. The said cuter end 11 is recessed, and the wall of the recess is pierced by holes 13 so as to give access to the chamber 5 when the parts are in. the position shown. The part 8 of the anti-leak device is urged inwardly from the nozzle i by means of a spring 14: which abuts against said nozzle and against the end' face of the part 8 which is fitted with a threaded flanged collar 17 to provide adequate bearing surface, the cylindrical member 9 serving as a guide for the springl i being flanged as'shown at'lS so 'as' tobe withdrawn away from the nozzle i by the fiange of the part 1'4" when the latter is lifted by the spring lei. It is to be noted that'the inner edge of the central recess 12 of the nozzle 14 is cut away to form a conical seating 15 with which a conicalface 16 formed on the part 6" is adapted to engage; Then the nozzle l is unscrewed, all the parts within the chamber 5 can be withdrawn if desired for refitting or repair.

The chamber 5 is situated within the pressure, chamber 23 and access is given thereto by a radial tube 2 L terminatingin a filter 25.

In use liquid is fed to the pressure chainber onboth strokes of the piston 2 through um tube 26"leadii1gfrom the chamber 22.

The said liquid falls to the bottom of the chamber 2.3, it being understood that the syringe is used inaposition such that the tube 2% is directed downwardly.

' In these circumstances, owing to the. pressure of the air cushien the chamber. 23, a

continuous pressure is maintained tending to drive the liquid; upthe: tube 24.

hen the} parts. are in the position shown, the liquid'passing up thetube. 24fhas free egress out of the chamber 5. through the holes 13 passage 'l z'offthe nozzle 4, and it isfto be understood'that unlessde' ressed b the piston the. parts, are inaintai ne in the position shown by the spring leak from the pump ch an iber. to the chamber 5. being oilectively prevented by" theconical faces 3. 8., controlled by. the spring 14.

When the syringe is intended to be stored the piston is depressed below the position shown and engages with the 'part'fldepre ssing the latter and causingfthe part 11 through the intermediary or the spring 10 to be forced downwardly until the face ldfirmly engages against the seating 15, Inthis position the holes 13"have entered the passage in the nozzle 1, and the chamber 5 is maintained closed against'lealir. Eurthenthe engaging conical faces 16, 15, efl'ectiyely close the passage 12. against liquid; escaping pastthe wallet thepart ll. stated, the piston is adapted to be held in the said: closing positionby any known means, Owin to. the, provision of. the spring. 10: actuating: the closing element 1 1, the device includes an elastic link which ensures proper closure oi the nozzle in case the length of the piston. rod is a little over or under the designed length when held down by the locking device.

I claim 1. A syringe, comprising a casing, a partition extending transverse the casing and dividingthe easing into a liquid chamber and an air cushion chamber, each of the full sectional area of the casing, a housing extending lengthwise the casing and through both chambers, a piston reciprocal in the housing, a nozzle carried by the housing, and means operablein the housing to control communication between the air chamber and said nozzle in accordance with the position of the piston.

A syringe, comprising tition extending transverse the casing and dividing thecasing into a liquid chamber an air cushion chamber, each of the full sectional area of the casing, a housing extending lengthwise the casing and throu h a casing, a parboth chambers a piston reciprocal in tie housing, a nozzle carried bythe housing, and means operable in the housing to, control communication between the air chamber and said nozzle in accordance with the position of the piston, said means serving when the piston is fully depressed to close communication between the air cushion chamber and the nozzle.

3. In a syringe, a casing, a pump housing extending throughput the length of the easing, a delivery nozzle carried by the housing and projecting beyond the casing, a par tition arranged inthe casing and encircling thehousing to divide the casing into a liquid chamber arid an air cushion chamber, each surrounding the housin and oi the, full transverse dimensionof the casing, a piston operable in the housing to deliver fluid from the liquid ehjaiiiber to h a r s on, hamber, a Communication between the air cushion chamber and the housing, valve mechanism normally permitting communication between the housing and nozzle in the operative. positions of thepiston, said valve niechanism, being operable by the piston in one position of the latterto cut oil' communication between the housing and nozzle.

4. In a syringe, a casing, a pump housing extendin throughout the length of the. casing, a delivery nozzle carried by the housing and projecting beyond the casing, a partition arranged in the casing and encircling the housing. to divide .the easing into a liquid chamber and. an air cushion chamber, each surrounding the housing and oi the full transverse dimension of the casing, a piston operable in the housing to deliverfluid from the liquid chamber to the air cushion cha nbe r, a communication between the air cushion chamber and the housing, a plunger operable in the nozzle and" adapted in one position to establish communication between the housing and nozzle and adapted in another position to out off said communication, means for holding the plunger in position to establish said communication in the pumping operations of the piston, and means operable by the piston in a predetermined position to actuate the plunger to cut off said communication between the nozzle and housing.

5. In a syringe, a casing, a pump housing extending throughout the length of the cas ing, a delivery nozzle carried by the housing and projecting beyond the casing, a partition arranged in the casing and encircling the housing to divide the easing into a liquid chamber and an air cushion chamber, each surounding the housing and of the full transverse dimension of the casing, a piston operable in the housing to deliver fluid from the liquid chamber to the air cushion chamber, a communication between the air cushion chamber and the housing, a plunger operable in the nozzle and adapted in one position to establish communication between the housing and nozzle and adapted in another position to cut off said communication, a spring for normally holding the plunger in position to establish communication between the nozzle and housing in the pumping operations of the piston, and a member to be operated by the piston in a predetermined position of the latter to move the plunger to out off communication between the housing and nozzle.

In testimony whereof I affix my signature.

LEONARD M. JONES. 

